The RSR rocker shaft seals are a great insurance policy against leaky valve covers- IF installed properly. Delicate, square-edged, and very finicky, the seals prove to be a serious installation challenge- ALL 24 of them! Until now. STOMSKI RACING's SR029 -RSR Rocker Shaft Seal Installation Tool allows for easy, smooth, and kink-free installation of the seals, providing optimal leak-free installation and making for a much quicker assembly. CNC brass.